promise初体验

window.jQuery = function(nodeOrSelector) {
    let nodes = {}
    nodes.addClass = function() {}
    nodes.html = function() {}
    return nodes
}

window.jQuery.ajax = function({url,method,body,headers}) {
    return new Promise(function(resolve,reject) {
            let request = new XMLHttpRequest()

            request.open(method, url) //配置request
            for(let key in headers) {
                let value = headers[key]
                request.setRequestHeader(key, value)
            }
            request.onreadystatechange = () => {
                if(request.readyState === 4) {
                    if(request.status >= 200 && request.status < 300) {
                        resolve.call(undefined, request.responseText)
                    } else if(request.status >= 400) {
                        reject.call(undefined, request)
                    }
                }
            }
            request.send(body)
        })
    }

window.$ = window.jQuery

mybutton.addEventListener(‘click‘, (e) => {
    window.jQuery.ajax({
        url: ‘/xxx‘,
        method: ‘get‘,
        headers: {
            name: ‘Rony‘
        }
    }).then(()=>{console.log(‘suc‘)},
        ()=>{console.log(‘fail‘)})
})